Disposable broom core and bristle assembly



Dec. 31, 1968 L. L. LECHENE 3,418,674

DISPOSABLE BROOM CORE AND BRISTLE ASSEMBLY Filed Nov. 30, 1967 unvsuron LEO L. LECHENE 04%, M ATTORNEYS United States Patent 3,418,674 DISPOSABLE BROOM CORE AND BRISTLE ASSEMBLY Leo L. Lecliene, RD. 1, Box 364, Patton, Pa. 16668 Filed Nov. 30, 1967, Ser. No. 687,039 1 Claim. (Cl. 15-182) ABSTRACT OF THE DISCLOSURE A disposable core and bristle assembly for street sweeping brooms, which includes a moulded plastic core with exterior sprial groove along its length, with plastic adapter hubs secured within its ends, a series of bristle mats formed into U-shape and at their apices nested end to end in said groove and secured therein by a plastic cable wound therearound, each mat including a plurality of parallel engaging plastic coplanar bristles transversely fused together at their central portions; and the method of making said core and bristle assembly.

The present invention relates to a disposable core and bristle assembly for street sweeping brooms, and represents an improvement in the core construction disclosed in my copending patent application, Ser. No. 623,264, filed Mar. 15, 1967, entitled Broom Core Winding Machine.

Heretofore, in the assembly of street sweeping brooms, the power driven core including spiral external groove, normally mounts a series of bristles retained within the spiral groove by a suitable cable and wherein the core sections are metalic and extremely heavy.

Bristle assemblies with plastic material have heretofore been employed but with the use of the heavy core body, excessive weight, and increased friction is applied to the bristles in use with the result that an incorrect sweeping action is achieved with respect to the ground surface.

It is an object of the present invention to provide an improved prefabricated disposable broom core and bristle assembly by which the core itself is constructed of a moulded plastic material such as polypropylene, and wherein the spiral groove in its exterior surface is moulded thereinto as a part of the manufacturing process. Heretofore, the application of a spiral groove to the metallic core has been difficult and time consuming.

It is therefore another object of the present invention to provide a simplified and inexpensive and exceedingly lighter broom core and bristle assembly, by Which the weight is reduced from a conventional 200 lbs. to approximately 50 lb.

Heretofore, in the manufacture of bristle assemblies, with such cores, the spiral grooves have a pitch of approximately 1 /4 to 2", and there have been nested within such groove multiple layers of bristles in order to provide a homogenous and uniform complete brush and bristle assembly.

It is'an object of the present invention to reduce the pitch approximately to A3", so that the bristles are wound in a tighter arrangement, and wherein a single layer of bristles may be employed thus saving approximately 20% of the plastic material involving the bristles, and adding at least 20% efficiency to the broom. By lightening the broom assembly, since a plastic core is provided, there is less weight and pressure upon the individual bristles, with the result that the bristles provide an improved flicking action, and a higher sweeping efiiciency than has ever been achieved with the old type of metallic heavy broom cores.

It is another object of the present invention to provide a disposable plastic broom core assembly which may be of unit construction or sectional with the portions adhered 3,418,674 Patented Dec. 31, 1968 together to form a unit broom core body, and wherein the spiral groove is moulded thereinto, as an integral part of the broom core body.

These and other objects will be seen from the following specifications and claims in conjunction with the appended drawing in Which:

FIG. 1 is a fragmentary prespective view of a partially assembled broom core and bristle assembly, illustrating the method of assembling the bristle mats upon the broom core, and the step of securing the same thereon.

FIG. 2 is a fragmentary partially sectioned view on an increased scale illustrating the mounting and securing of the bristle mats upon said core.

FIG. 3 is a longitudinal section of one form of the present prefabricated disposable broom core.

FIG 4 is an end elevational View thereof, considering said core as a unit assembly.

FIG. 5 is a similar end elevational view with the core made up of two assembled sections.

FIG. 6 is a fragmentary sectional view of a modified core body.

FIG. 7 is a fragmentary longitudinal section of a modified broom core assemb'y.

FIG. 8 is a fragmentary section taken in the direction of arrows 88 of FIG. 7.

FIG. 9 is a schematic view illustrating the flicking characteristic of the present bristle assembly.

FIG. 10 is a similar view illustrating the poor flicking characteristic of conventional bristle assemblies.

It will be understood that the above drawing illustrates several preferred embodiments of the invention, and that other embodiments are contemplated within the scope of the claims hereafter set forth.

Referring to the drawings, FIG. 1 illustrates fragmentarily and schematically a partially completed prefabricated broom core and bristle assembly, in accordance with the present invention, the broom being generally indicated at 11, the core at 12. The broom is made up of a plurality of bristle mats of rectangular form as shown at 15, with each rnat consisting of a series of parallel engaging p astic bristles 14, arranged side by side, heat welded or fused together at their mid portions, and formed into a general V-shape or U-shape, such as shown in FIG. 1. These bristle mats 15 are nested within the continuous sprial groove 13 formed within prefabricated plastic core 12, and held therein by the plastic rope or cable 16, preferably of polypropylene. This is unwound under tension from drum 17, and over the bight portion of the individual bristle mats 15 for securely anchoring the same end to end within spiral groove throughout the length of disposable core 12.

Referring to FIG. 2, the plastic disposable core body 18, fragmentarily shown, is a moulded element with a spiral groove 13 moulded therein, as further shown in FIGS. 3, 6, and 7.

The application of the bristle mats 15 to the core spiral groove 13 is shown in further detail in my copending patent application 623,264, filed Mar. 15, 1967, entitled Broom Core Winding Machine. There is merely shown in FIG. 2 a fragmentary illustration which illustrates schematically and fragmentarily the yoke 19 which is in the nature of a follower, and which mounts the rollers 20 which ride within the spiral groove 13, in advance of the bristle mats and includes the yieldable retractor arm 21, which holds the assembled bristle mats in a retracted position during winding to facilitate the application of the succeeding mats into the spiral groove 13 during continuous rotation of the core 12, and with the winding under tension of the plastic rope 16 over the bight portions of the mats 15 for securing the same within the spiral groove, completing the sweeping brush assembly.

It is understood that the rope or cable 16 as initially started within the groove 13 is clamped or otherwise anchored at one end of the core 12, and at the end of the winding operation the other end of the cable 16 is clamped or secured to the core 12 at the opposite end of spiral groove 13.

One form of core assembly is shown in FIGS. 3 and as at 22, designating a core assembly, having a cylindrical bore 23, and within the opposite ends thereof adapter hubs 24, fixedly secured therein as by an adhesive 25, such as a polyester resin. In the preferred embodiment of the invention the core body 18 is formed of a plastic material as for example, polypropylene, and wherein the spiral groove 13 is moulded thereinto as a part of the moulding process. The core 18, FIG. 3 may be blowmoulded in one piece, such as illustrated in FIG. 4, as at 35, or may be pressure moulder into a pair of semicylindrical sections 31 and 32, FIG. 5, the sections being adhesively interconnected at their parting line 33 by a suitable adhesive, such as a polyester resin. The plastic core body 18 may be moulded as a unit, using centrifugal moulding or could be a hand layup, with a fiber glass reinforcement, although other reinforcement medium may be employed, such as clay or asbestos.

The respective adapter hubs are also of a plastic material, such as polypropylene, and include axial tubular shanks 26 adapted to receive the correct size of adapter sleeve 27, which in turn receives drive shaft 28 or driven shaft 30 respectively anchored in assembled relation, as shown by the pin 29, FIG. 3. This is illustrative of merely one form of transmitting power from the drive shaft 28 forming a part of the street sweeping broom assembly to the broom core and bristle assembly 22 as axially journalled at 30, fragmentarily shown.

Fasteners 34 are shown providing the means by which anchoring rope of polypropylene 16 is secured to opposite ends of the core body, for illustration.

Instead of a multiple section core, as shown in FIGS. 3 and 5, the core could be blow-moulded as a unit core as at 35, and wherein it appears that the adapter hubs may be moulded as an integral part thereof as desired.

Modification A modified plastic broom core is designated at 38, FIG. 7, which in addition to the external spiral groove 13 above described, includes a corresponding internal spiral groove forming a part of the bore 37, in opposing registry to the exterior spiral groove 13, as achieved during a blowmoulding process in the formation of the prefabricated plastic broom core 38. A modified form of plastic adapter hubs are shown at 39, cemented as at 25 within the end portions of the core body 36. Each of the hubs 39 has upon its exterior a transverse drive flange 40 adapted to receive the bifurcated end portions 42 of the corresponding drive shaft assembly 41 and driven shaft assembly 44, transversely secured thereto by the fasteners or pins 43, the numeral 45 being intended to schematically indicate the journal support for the driven shaft 44.

The present prefabricated broom core and bristle assembly of FIG. 1 is disposable due to the moderate lower cost of production. Cost is furthermore reduced in view of the reduced pitch distance between turns of the spiral groove 13 which in the illustrative embodiment is approximately By thus reducing the pitch distance from a conventional pitch of approximately 2", the individual bristles, while closer together, act independently since one layer of bristle mat 15 is employed. There is thus a better distribution of the bristle elements in an assembly with more precision which eliminates voids and adds approximately 20% efficiency to the broom, employing 20% less plastic material, and reducing the overall weight of the broom from 200 lbs. to 50 lbs., approximately, i.e. 75% reduction in the conventional weight.

This is important because it has an effect upon the flicking action of the individual bristles 14, as illustrated schematically in FIGS. 9 and 10.

FIG. 10 illustrates the conventional construction of broom core and bristle assembly of a weight of approximately 200 lbs., and wherein the bristle 14' is shown to have a considerable bend throughout the area where it engages the ground surface G, forming a part of the street sweeper assembly generally indicated at 46 schematically, and including the motorized conveyor 47 into which particles of dirt received from the bristles 14' are transferred into the storage bin 48.

In the conventional construction shown in FIG. 10, due to the severe bending of the bristle element 14, there is little or no flicking action with the result that the bristle elements 14 merely rearrange the dirt as it passes thereover, as distinguished from the illustration in FIG. 9, wherein the present bristles 14, due to the substantial reduction in weight of the bristle and core assembly take on a slightly different but greatly improved working shape, as designated at 14, FIG. 9. Here there is provided a substantially improved flicking action, since the bristles 14, acting individually are adapted upon rotation of the broom core to flick the particles of dirt onto the motorized conveyor 47 and into the storage bin 48 of a street sweeper, such as designated at 46', schematically. It is believed that FIG. 9 as compared with FIG. 10 points up the improved flicking action which is achieved by the present broom core and bristle assembly.

Polypropylene has been explained as a preferred form of plastic material for making up not only the bristle core, as prefabricated, but the bristles themselves. Alternately, the bristle core could be constructed of any polyester plastic, fiber glass reinforced, such as shown in FIGS. 3 and 7, for illustration.

Method The present method as schematically illustrated in FIGS. 1 and 2, includes the following steps:

(1) Moulding an elongated plastic core body, which has an external spiral groove in its outer surface throughout its length.

(2) Forming a series of bristle mats 15, each mat being rectangular and including a plurality of coplanar loose plastic bristles 14 parallel to each other, centrally fused together crosswise of the bristles, FIG. 1.

(3) Said mat being formed into U-shape.

(4) Applying the mid portion of said mats 15 succesdsively into the spiral groove 13, throughout its length, an

5) Snugly winding under tension the plastic rope 16, which at one end is anchored to said core body at 34, along and throughout said spiral groove, and anchoring ropeat its outer end at 34 to said body at the other end of said spiral groove.

It is contemplated as a part of the assembly process that the core body may he of a unit plastic construction, FIG. 4, or may be constructed of sections 31 and 32 FIG. 5, and adhesively joined as at 33.

The moulding step for the core body above may include the formation of the plastic adapter hubs 24 as a part of the moulding operation using blow-moulding for illustration or these hubs may be assembly and adhesively secured as at 25, in a separate step in advance of the bristle mat assembly operation.

Having described my invention, reference should now be had to the following claim.

I claim:

1. In a street sweeping broom, an elongated disposable cylindricial moulded plastc core body, there being a continuous exterior spiral groove in its outer surface throughout its length;

axially apertured plastic adapter hubs secured within the outer ends of said body to journal the body and to receive rotative power;

a series of bristle mats formed into U-shape and nested end to end throughout said groove;

each mat consisting of a plurality of loose coplanar stiff, yet resilient plastic bristles arranged in parallel engagement and crosswise to the length of the mat, the central portions of said bristles being fused together transversely;

and a rope of plastic material anchored to said body at one end of said spiral groove, tightly wound around the bight portions of the said mats, within and throughout the length of said groove anchoring said mats therein;

the other end of the rope anchored to said body at the other end of said groove, said hubs being of a cupshape, snugly nested into and adhered to said core body;

and a centrally arranged elongated radial drive flange upon the outer surface of each hub and secured thereto, adapted for connection to an axial drive and journal means respectively, said core being the sole support for said bristles.

References Cited FOREIGN PATENTS 7/ 1967 Great Britain.

15 PETER FELDMAN, Primary Examiner.

US. Cl. X.R. 

